But when the polls close in Washington and Oregon at 8 p.m. tonight, low-car Portlanders should also be looking north.

In Clark County, the Columbia River Crossing project isn’t a highway expansion controversy, because almost everybody favors highway expansion. Instead, it’s a battle over whether light rail and auto tolling should be parts of a compromise. The three votes below – especially the first, which could go either way – will call Clark County voters more directly to the bridge question than any time in last 18 years.

Proposition 1 (pro-CRC). This 0.1 percentage point sales tax hike in urban areas would actually just help C-Tran pay for light rail and high-capacity bus transit operations, money that C-Tran might be able to do without. But Clark County representatives in both the federal and state legislature have decided to treat it as a referendum on the Columbia River Crossing as planned – with tolls, rail and eight lanes of through traffic. If Proposition 1 fails, Clark County could have to wait another decade for high-capacity transit – and the pro-highway lobby will have a significantly harder time persuading Clark County lawmakers to carry water for them in the legislature.

There’s also strong disagreement over the crossing project on Clark County’s three-member commission.

Clark County Commission, at-large vote: Joe Tanner (D, pro-CRC) vs. Tom Mielke (R, anti-CRC). Tanner is a centrist Democrat, which in Clark County means that he tends to want somewhat looser land-use restrictions and a big new highway bridge partly funded by tolls. Mielke is a right-wing Republican incumbent who opposes land-use restrictions, and staunchly opposes spending gas-tax dollars on a bridge replacement he sees as less important than highway expansions elsewhere.

Clark County Commission, at-large vote: Marc Boldt (R, pro-CRC) vs. David Madore (R, anti-CRC). Boldt is a center-right Republican incumbent who’s bucked his party to back a bridge he sees as a pro-business compromise. Madore is a single-issue local businessman running to oppose tolls, rail and urban planning. Without a Democrat on the ballot, Boldt looks like the favorite, but Madore’s showing is more or less a pure measure of voters’ temperature on the bridge.

As the returns roll in, one important note: Washington voters can mail their ballots as late as today, so in Clark County the slowest ballots to arrive are the ones from the most rural and the most heavily anti-CRC areas. If any of the pro-CRC races finishes less than four points ahead during tonight’s results, nothing’s solid yet.

For CRC watchers, another big question of the night is Oregon’s legislature, where pro-transit Democrat and CRC supporter Tina Kotek is hoping to become Speaker of the House and set the agenda for the crucial 2013 legislative session.

But tonight’s clearest action on the region’s biggest transportation project is going to come from the north side of the Columbia. And you can bet the region’s other politicians will be watching.